Vessel transit in ice-covered waters poses unique challenges in safe and efficient motion planning. When the concentration of ice is high, it may not be possible to find collision-free trajectories. Instead, ice can be pushed out of the way if it is small or if contact occurs near the edge of the ice. In this work, we propose a real-time navigation framework that minimizes collisions with ice and distance travelled by the vessel. We exploit a lattice-based planner with a cost that captures the ship interaction with ice. To address the dynamic nature of the environment, we plan motion in a receding horizon manner based on updated vessel and ice state information. Further, we present a novel planning heuristic for evaluating the cost-to-go, which is applicable to navigation in a channel without a fixed goal location. The performance of our planner is evaluated across several levels of ice concentration both in simulated and in real-world experiments.

翻译：冰覆盖水域中的船舶航行对安全高效的运动规划提出了独特挑战。当冰密度较高时，可能无法找到无碰撞轨迹。相反，若冰体较小或接触发生在冰缘附近，则可通过推动冰体来开辟航道。本研究提出了一种实时导航框架，旨在最小化船舶与冰体的碰撞风险及航行距离。我们采用基于格子的规划器，其代价函数包含船-冰相互作用模型。为应对环境的动态特性，我们基于更新的船舶与冰况信息，以滚动时域方式规划运动。此外，我们提出了一种新颖的规划启发式方法来评估剩余代价，该方法适用于无固定目标点的航道导航场景。通过模拟实验和真实环境实验，我们评估了所提规划器在不同冰密度条件下的性能。